Changed Object.keys to return strings for element indices.

src/heap.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1564 matching lines @@
   int int_value = FastD2I(value);
   if (value == FastI2D(int_value) && Smi::IsValid(int_value)) {
     return Smi::FromInt(int_value);
   }
 
   // Materialize the value in the heap.
   return AllocateHeapNumber(value, pretenure);
 }
 
 
+Object* Heap::NumberToString(Object* number) {
+  Object* cached = GetNumberStringCache(number);
+  if (cached != undefined_value()) {
+    return cached;
+  }
+
+  char arr[100];
+  Vector<char> buffer(arr, ARRAY_SIZE(arr));
+  const char* str;
+  if (number->IsSmi()) {
+    int num = Smi::cast(number)->value();
+    str = IntToCString(num, buffer);
+  } else {
+    double num = HeapNumber::cast(number)->value();
+    str = DoubleToCString(num, buffer);
+  }
+  Object* result = AllocateStringFromAscii(CStrVector(str));
+
+  if (!result->IsFailure()) {
+    SetNumberStringCache(number, String::cast(result));
+  }
+  return result;
+}
+
+
 Object* Heap::NewNumberFromDouble(double value, PretenureFlag pretenure) {
   return SmiOrNumberFromDouble(value,
                                true /* number object must be new */,
                                pretenure);
 }
 
 
 Object* Heap::NumberFromDouble(double value, PretenureFlag pretenure) {
   return SmiOrNumberFromDouble(value,
                                false /* use preallocated NaN, -0.0 */,
@@ skipping 2232 matching lines @@
   for (int i = 0; i < kNumberOfCaches; i++) {
     if (caches_[i] != NULL) {
       delete caches_[i];
       caches_[i] = NULL;
     }
   }
 }
 
 
 } }  // namespace v8::internal